FED-M3-05 — Federation List Verb Scratchpad

Objective

Implement POST /api/federation/v1/list/:resource.

Wire FederationAuthGuard → FederationScopeService → read-only list query layer.
Apply max_rows_per_query row cap and return pagination metadata when truncated.
Tag returned rows with _source: "local".
Keep audit writes deferred to M4.
No request/response body persistence.

Added ListController under apps/gateway/src/federation/server/verbs/.
Added FederationListQueryService as the read-only query layer and native RBAC evaluator.
Query resources supported in M3 list path:
- tasks: project/mission scoped tasks visible through personal/team project access.
- notes: non-empty mission_tasks.notes rows visible through personal/team mission access.
- memory: user-owned insights and preferences rows.
- credentials / api_keys: denied by native RBAC in M3 even if present in scope; sensitive-resource implementation is not part of FED-M3-05.
Cursor pagination uses an opaque base64url keyset cursor over (createdAt, id); DB reads fetch at most limit + 1 rows per resource query.
Reviewer isolation fix: mission_tasks.notes rows are always constrained by missionTasks.userId = subjectUserId and accessible mission IDs; team scope narrows missions but never widens to other users' mission task notes.
Follow-up review fix: memory listing now uses deterministic table-block pagination (insights first, then preferences) with cursor source metadata, so one table's cursor is never applied to the other.
Follow-up hardening: missing auth-guard context returns a structured federation unauthorized envelope; unsupported resources and non-encodable truncated cursors throw instead of silently crashing/truncating.

pnpm --filter @mosaicstack/gateway test -- list.controller.spec.ts list-query.service.spec.ts — PASS (16 tests, including PGlite regression coverage for team-scoped notes isolation, unauthorized mission notes exclusion, includePersonal: false, deterministic memory pagination, missing context envelope, unsupported resource, and cursor encode failure).
pnpm --filter @mosaicstack/gateway typecheck — PASS.
pnpm --filter @mosaicstack/gateway lint — PASS.
pnpm format:check — PASS.
pnpm typecheck — PASS (41/41 turbo tasks).
pnpm lint — PASS (23/23 turbo tasks).
pnpm --filter @mosaicstack/gateway test — FAIL in pre-existing/live-DB integration suite: apps/gateway/src/__tests__/cross-user-isolation.test.ts cleanup cannot connect to local PostgreSQL on localhost:5433. New list tests pass; failure is outside FED-M3-05.

~/.config/mosaic/tools/codex/codex-code-review.sh --uncommitted — PASS after follow-up remediation; approve, no findings.
~/.config/mosaic/tools/codex/codex-security-review.sh --uncommitted — PASS after follow-up remediation; risk level none, no findings.
Security-review note: read-path audit logging remains intentionally deferred to M4 per orchestrator clarification and FED-M3-05 scope.